Gen 4 update to the G21 with dual recoil spring and modular back straps for the .45 ACP full-size platform. Type: Pistol Action: Semi-Automatic Caliber: .45 ACP Capacity: 13 Year introduced: 2013, Austria Weight: 29.28 oz Overall length: 7.59" Status: Active Intended use: Service, Law Enforcement, Home Defense